I've seen quite a few Postman alternatives pop up recently (quite curious what's the reasoning behind that?). Currently I'm mostly using Hoppscotch - also open-source with pretty sweet UI, and Thunder Client in VS Code.
That said, I'd consider switching for type-safety (or more specifically auto-completion) if there was an ability to e.g. import existing OpenAPI schema and automatically pick up the types.
My guess at the Postman-alikes. Postman has evolved way past its original usefulness and is aggressively trying to push enterprise features and anything to make the business sustainable. I'm not mad at them for that but eventually you remember that you just wanted a graphical curl to mess with, not a team secret manager with workspaces and a test runner etc.
The basic functionality starts off pretty easy to build so there's a large pool of people who decide to take a crack at it.
That said, I'd consider switching for type-safety (or more specifically auto-completion) if there was an ability to e.g. import existing OpenAPI schema and automatically pick up the types.